Section 1 (3-1) Volcanoes and Plate Tectonics

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Vocabulary

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volcano- a place on Earth where it is weak and lava comes out there.
magma- a molten thing which includes gas, water, and molten rock.
lava- a magma which came out to the surface.
Ring of Fire- the major volcanic belt where a lot of volcanoes comes in circle.
island arc- a line of island which is created by same volcano.
hot spot- a big place underground where magma is stored.

Outline

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What is a volcano?

• Where the volcanoes form are the weak spot on Earth where the lava comes out.
• When lava cools, it becomes to solid rock.
• Volcano is one of the constructive forces.

Location of Volcanoes

• There are about 600 volcanoes on land.
• There are many more volcanoes underwater than on land.
• Volcanoes occurs in belts.
  • The major belt is Ring of Fire.
• Most volcanoes are formed near plate boundries.
  • Near the subduction zone, and plate boundries.

Volcanoes at Diverging Plate Boundries

• Most volcanoes form near the plate boundries.
  • It is because the plates melt and the molten material comes up to surface and becomes magma.
• The volcanoes underwater on plate boundries may form a strings of island called island arc.
• The major countries with volcanoes are Japan, Indonesia, New Zealand, and some other countries.

Hot Spot Volcanoes

• A volcano which is not near the plate boundries all have hot spot.
  • The hot spot has a lot of magma for the volcano to erupt.
  • The Hawaiian Islands are made from one volcano which has a hot spot.
  • Hot spot can also be under the continents.

Diagram